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Shanshan Zhou - One of the best experts on this subject based on the ideXlab platform.
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Bioleaching of different copper sulfides by Acidithiobacillus ferrooxidans and its adsorption on minerals
Hydrometallurgy, 2013Co-Authors: Yingbo Dong, Xiaofang Xu, Shanshan ZhouAbstract:Abstract The bioleaching of five different copper sulfide minerals (djurleite, bornite, Covellite, massive sulfide copper and porphyry chalcopyrite) by Acidithiobacillus ferrooxidans ( At.f LD-1) and the adsorption behavior of At.f LD-1 on mineral surfaces were investigated. Bioleaching experiments show that the copper extraction of the five different copper sulfide minerals increased by adding proper amounts of ferrous ions in the early leaching period. The copper extraction followed the order djurleite > bornite > massive sulfide copper > Covellite > porphyry chalcopyrite. The bacterial adsorption experiments indicate that the adsorption isotherms can be well described by Langmuir adsorption isotherm model. Under pH 2 and adsorption equilibrium, the bacterial adsorption quantity on the five copper sulfide minerals showed the same order as that of copper extraction.
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comparative study on the bioleaching biosorption and passivation of copper sulfide minerals
International Biodeterioration & Biodegradation, 2013Co-Authors: Yingbo Dong, Xiaofang Xu, Yue Zhang, Shanshan ZhouAbstract:Abstract The bioleaching, biosorption and passivation of five different types of copper sulfide minerals (djurleite, bornite, Covellite, pyritic chalcopyrite, and porphyry chalcopyrite) by Acidithiobacillus ferrooxidans ( At.f LD-1) were investigated in this paper. The bioleaching experiments showed that copper extraction followed the order djurleite > bornite > pyritic chalcopyrite > Covellite > porphyry chalcopyrite. The bacterial adsorption experiments indicated that the bacterial adsorption quantity onto the five copper sulfide minerals had the same order as that of copper extraction. SEM analysis showed that bacterial distribution on the djurleite, bornite, and Covellite was uniform and that on the pyritic chalcopyrite and porphyry chalcopyrite was uneven (distributed as continuous chain structure). Zeta potential analysis showed that the zeta potentials of copper sulfide minerals after interaction with At.f LD-1 cells changed to varying degrees. The variation degree of the zeta potentials of the five copper sulfide minerals showed the same order as the bacterial adsorption quantity on the five copper sulfide minerals. The main passivation layers on the residues of djurleite and bornite were both jarosite, and that the passivation layers on the residues of Covellite, pyritic chalcopyrite, and porphyry chalcopyrite were Cu 4 S 11 , S 8 , and Cu 4 Fe 2 S 9 , respectively. The inhibition ability of passivation layers followed the order Cu 4 Fe 2 S 9 > Cu 4 S 11 > S 8 > jarosite.
Yingbo Dong - One of the best experts on this subject based on the ideXlab platform.
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Bioleaching of different copper sulfides by Acidithiobacillus ferrooxidans and its adsorption on minerals
Hydrometallurgy, 2013Co-Authors: Yingbo Dong, Xiaofang Xu, Shanshan ZhouAbstract:Abstract The bioleaching of five different copper sulfide minerals (djurleite, bornite, Covellite, massive sulfide copper and porphyry chalcopyrite) by Acidithiobacillus ferrooxidans ( At.f LD-1) and the adsorption behavior of At.f LD-1 on mineral surfaces were investigated. Bioleaching experiments show that the copper extraction of the five different copper sulfide minerals increased by adding proper amounts of ferrous ions in the early leaching period. The copper extraction followed the order djurleite > bornite > massive sulfide copper > Covellite > porphyry chalcopyrite. The bacterial adsorption experiments indicate that the adsorption isotherms can be well described by Langmuir adsorption isotherm model. Under pH 2 and adsorption equilibrium, the bacterial adsorption quantity on the five copper sulfide minerals showed the same order as that of copper extraction.
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comparative study on the bioleaching biosorption and passivation of copper sulfide minerals
International Biodeterioration & Biodegradation, 2013Co-Authors: Yingbo Dong, Xiaofang Xu, Yue Zhang, Shanshan ZhouAbstract:Abstract The bioleaching, biosorption and passivation of five different types of copper sulfide minerals (djurleite, bornite, Covellite, pyritic chalcopyrite, and porphyry chalcopyrite) by Acidithiobacillus ferrooxidans ( At.f LD-1) were investigated in this paper. The bioleaching experiments showed that copper extraction followed the order djurleite > bornite > pyritic chalcopyrite > Covellite > porphyry chalcopyrite. The bacterial adsorption experiments indicated that the bacterial adsorption quantity onto the five copper sulfide minerals had the same order as that of copper extraction. SEM analysis showed that bacterial distribution on the djurleite, bornite, and Covellite was uniform and that on the pyritic chalcopyrite and porphyry chalcopyrite was uneven (distributed as continuous chain structure). Zeta potential analysis showed that the zeta potentials of copper sulfide minerals after interaction with At.f LD-1 cells changed to varying degrees. The variation degree of the zeta potentials of the five copper sulfide minerals showed the same order as the bacterial adsorption quantity on the five copper sulfide minerals. The main passivation layers on the residues of djurleite and bornite were both jarosite, and that the passivation layers on the residues of Covellite, pyritic chalcopyrite, and porphyry chalcopyrite were Cu 4 S 11 , S 8 , and Cu 4 Fe 2 S 9 , respectively. The inhibition ability of passivation layers followed the order Cu 4 Fe 2 S 9 > Cu 4 S 11 > S 8 > jarosite.
C Pogliani - One of the best experts on this subject based on the ideXlab platform.
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a comparison of bioleaching of Covellite using pure cultures of acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans or a mixed culture of leptospirillum ferrooxidans and acidithiobacillus thiooxidans
Hydrometallurgy, 2003Co-Authors: LUCIEN FALCO, C Pogliani, Gustavo Curutchet, E DonatiAbstract:The aim of this investigation was to determine the efficacy of Covellite bioleaching using pure cultures of Acidithiobacillus ferrooxidans or Acidithiobacillus thiooxidans and a mixed culture composed of At. thiooxidans and Leptospirillum ferrooxidans. The experiments were carried out in shake flasks with or without iron(II) (1 g/L as ferrous sulphate) at pH 2.0. Inocula of both iron-oxidising bacteria were obtained from cultures with iron(II) as the sole energy source, whereas At. thiooxidans inoculum was taken from a culture growing on sulphur. The solubilisation of copper in flasks inoculated with At. thiooxidans was greatly enhanced in the presence of additional iron(II) achieving 62% copper extraction in 30 days. This result agrees with a mechanism proposed recently. On the other hand, the effect of supplemental iron was not so important for Covellite leaching by the At. ferrooxidans culture and the mixed culture. Copper solubilisation by the At. ferrooxidans culture was nearly the same as that for the mixed culture (51% versus 55%).
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Anaerobic leaching of Covellite by Thiobacillus ferrooxidans
Applied Microbiology and Biotechnology, 1997Co-Authors: Edgardo R. Donati, C Pogliani, J. L. BoiardiAbstract:Thiobacillus ferrooxidans was able to grow under anaerobic conditions on copper sulphide with ferric ion as the electron acceptor. The dissolution of Covellite under these conditions (68% after 35 days) was higher than values observed aerobically in cultures with similar media composition and almost as high as under aerobic conditions without iron. From these results we propose a mechanism for anaerobic bioleaching of Covellite in the presence of ferric iron and speculate that it may occur in leach dumps where the oxygen concentration is, as reported elsewhere, very low.
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Bioleaching of Covellite using pure and mixed cultures of Thiobacillus ferrooxidans and Thiobacillus thiooxidans
Process Biochemistry, 1996Co-Authors: Edgardo R. Donati, C Pogliani, Gustavo Curutchet, P. TedescoAbstract:Abstract A high level of Covellite (CuS) dissolution was observed in systems containing Thiobacillus thiooxidans and iron. This activity was higher than with Thiobacillus ferrooxidans in the same medium and lower than that with T. ferrooxidans in the absence of iron. In mixed cultures, Covellite dissolution appeared to be associated with T. ferrooxidans in the presence of iron and sulphur but with T. thiooxidans when these were absent.
Edgardo R. Donati - One of the best experts on this subject based on the ideXlab platform.
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Anaerobic leaching of Covellite by Thiobacillus ferrooxidans
Applied Microbiology and Biotechnology, 1997Co-Authors: Edgardo R. Donati, C Pogliani, J. L. BoiardiAbstract:Thiobacillus ferrooxidans was able to grow under anaerobic conditions on copper sulphide with ferric ion as the electron acceptor. The dissolution of Covellite under these conditions (68% after 35 days) was higher than values observed aerobically in cultures with similar media composition and almost as high as under aerobic conditions without iron. From these results we propose a mechanism for anaerobic bioleaching of Covellite in the presence of ferric iron and speculate that it may occur in leach dumps where the oxygen concentration is, as reported elsewhere, very low.
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Bioleaching of Covellite using pure and mixed cultures of Thiobacillus ferrooxidans and Thiobacillus thiooxidans
Process Biochemistry, 1996Co-Authors: Edgardo R. Donati, C Pogliani, Gustavo Curutchet, P. TedescoAbstract:Abstract A high level of Covellite (CuS) dissolution was observed in systems containing Thiobacillus thiooxidans and iron. This activity was higher than with Thiobacillus ferrooxidans in the same medium and lower than that with T. ferrooxidans in the absence of iron. In mixed cultures, Covellite dissolution appeared to be associated with T. ferrooxidans in the presence of iron and sulphur but with T. thiooxidans when these were absent.
P. Tedesco - One of the best experts on this subject based on the ideXlab platform.
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Bioleaching of Covellite using pure and mixed cultures of Thiobacillus ferrooxidans and Thiobacillus thiooxidans
Process Biochemistry, 1996Co-Authors: Edgardo R. Donati, C Pogliani, Gustavo Curutchet, P. TedescoAbstract:Abstract A high level of Covellite (CuS) dissolution was observed in systems containing Thiobacillus thiooxidans and iron. This activity was higher than with Thiobacillus ferrooxidans in the same medium and lower than that with T. ferrooxidans in the absence of iron. In mixed cultures, Covellite dissolution appeared to be associated with T. ferrooxidans in the presence of iron and sulphur but with T. thiooxidans when these were absent.
